301661 divided by 81 
The aim is to understand the frequency of 81 in 301661.

Step 1:
81 goes into 3 0 times with a remainder of 3.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 3 after subtracting 0 from 3.
Include the next digit (0) from the dividend after 3, then repeat: 30 / 81

Step 2:
30 divided by 81 is 0 with a remainder of 30.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 30 after subtracting 0 from 30.
Include the next digit (1) from the dividend after 30, then repeat: 301 / 81

Moving on to step 3:
81 goes into 301 3 times with a remainder of 58.
Write down 3 as next digit of the result. 
Result so far: 3.0
The remainder is 58 after subtracting 243 from 301.
Take the next digit (6) from the dividend and append it to 58, then repeat: 586 / 81

Advancing to step 4:
81 goes into 586 7 times with a remainder of 19.
Put 7 as the next digit of the answer. 
Result so far: 37.0
Subtract 567 from 586 to get 19.
Grab the next digit (6) from the dividend, add it to 19, then carry on: 196 / 81

On to step 5:
The number 81 fits into 196 2 times, leaving a remainder of 34.
The next digit of our result is 2. 
Result so far: 372.0
Deduct 162 from 196 and we're left with 34.
Grab the next digit (1) from the dividend, add it to 34, then carry on: 341 / 81

Moving on to step 6:
If we divide 341 by 81, we get 4 and a remainder of 17.
Put 4 as the next digit of the answer. 
Result so far: 3724.0
Subtracting 324 from 341 leaves us with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Let's proceed to step 7:
81 can be fit into 170 2 times, resulting in a remainder of 8.
Write down 2 as next digit of the result. 
Result so far: 3724.2
Deduct 162 from 170 and we're left with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Advancing to step 8:
81 goes into 80 0 times with a remainder of 80.
The number 0 becomes the next digit in our result. 
Result so far: 3724.2
If we take 0 away from 80, we end up with 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Step 9:
800 divided by 81 is 9 with a remainder of 71.
The next digit of our result is 9. 
Result so far: 3724.209
Subtract 729 from 800 to get 71.
Since there are no more digits in the dividend, we add a zero to the remainder making it 710, and continue the process.

Let's proceed to step 10:
When dividing 710 by 81, we get 8 with a remainder of 62.
Record the quotient 8 as the next digit in the result. 
Result so far: 3724.2098
If we take 648 away from 710, we end up with 62.
Since there are no more digits in the dividend, we add a zero to the remainder making it 620, and continue the process.

Let's proceed to step 11:
81 can be fit into 620 7 times, resulting in a remainder of 53.
Use 7 as the next digit of our solution. 
Result so far: 3724.20987
The remainder is 53 after subtracting 567 from 620.
Since there are no more digits in the dividend, we add a zero to the remainder making it 530, and continue the process.

Let's proceed to step 12:
530 divided by 81 is 6 with a remainder of 44.
The next digit of our result is 6. 
Result so far: 3724.209876
The remainder is 44 after subtracting 486 from 530.
Since there are no more digits in the dividend, we add a zero to the remainder making it 440, and continue the process.

Advancing to step 13:
If we divide 440 by 81, we get 5 and a remainder of 35.
Record the quotient 5 as the next digit in the result. 
Result so far: 3724.2098765
Deduct 405 from 440 and we're left with 35.
Since there are no more digits in the dividend, we add a zero to the remainder making it 350, and continue the process.

Let's proceed to step 14:
81 can be fit into 350 4 times, resulting in a remainder of 26.
Use 4 as the next digit of our solution. 
Result so far: 3724.20987654
Subtract 324 from 350 to get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Our division results in 3724.20987654 with a remaining 2.6e-08.